"There's still a fair distance to travel to close the remaining gaps," Biden's national security adviser Jake Sullivan said Sunday.
With the ageing Ayatollah Ali Khamanei looking to secure the future of the regime, members of the Islamic Revolutionary Guard Corps are eyeing the presidency.
Iran's conservative-dominated parliament has made a legal complaint against Rouhani's government for agreeing a last-minute deal to secure international nuclear inspections.
The former president still believed he could make a deal with Tehran even as relations collapsed during his term.
Biden wants to reopen talks with Tehran and revive the Iran nuclear deal, but the presidents of both countries will have to overcome domestic opposition.
Iranian President Rouhani described both Trump and Hussein as "crazy creatures" who "imposed war" on Iran and its people.
Top Iranian officials have maintained a combative stance ahead of Biden's inauguration, as they prepare for negotiations to revive the beleaguered Iran nuclear deal.
A new Iranian president may also be better positioned in the system to negotiate more expansively than Rouhani. Washington shouldn't be rushing to recreate a reality from 2015 that doesn't exist anymore.
The Trump administration is turning the screws on Tehran, seeking to collapse Iran's economy before the end of the president's term.
The president said Iran would look to expand ties with neighbors once Trump is out of office, and claimed victory over the White House's "maximum pressure" campaign.
"The new U.S. administration should reconsider its inhumane behaviors toward other countries," Iranian President Hassan Rouhani said.
Foreign Minister Javad Zarif criticized the U.S., claiming sanctions have cut off food and medical supplies desperately needed in a pandemic.
"We have made great progress in the field of strategic and deterrent weaponry," Iranian President Hassan Rouhani said.
Iranian President Hassan Rouhani called for a nationwide halt on large gathering like weddings in order to curb the rise in coronavirus infections.
The Iranian government on Sunday mandated that everyone wear masks in public to curb the spread of the pandemic.
The Iranian president condemned President Trump's handling of the crisis, even though the regime in Tehran killed hundreds of people when suppressing anti-government demonstrations last year.
The Trump administration should follow the Monroe Doctrine and prevent Iranian meddling in our hemisphere.
Ayatollah Hashem Bathaei-Golpaygani was a member of the Assembly of Experts, which selects the country's supreme leader.
"In pursuing the case of the downed plane, justice will be implemented irrespective of any circumstances," Iran's judiciary chief said.
"Instead of caving, Iran is moving step by step out of the nuclear deal and in recent months it hit six ships, attacked Saudi oil facilities and set fire to the U.S. embassy in Baghdad," Chris Wallace pointed out.
Thousands took to the street, calling on Supreme Leader Ali Khamenei to resign.
Commander Amir Ali Hajizadeh revealed an operator made the decision to fire at the aircraft in 10 seconds.
All 176 passengers and crew on board the Ukrainian Airlines flight died in the crash.
Ali Akbar Velayati said that the U.S. "took a foolish move" by assassinating Qassem Soleimani "and they must leave the region."
"Be cautious before going to public places," the Chinese embassy in Washington warned its citizens.
An Iranian government spokesperson blamed the "bullying policy" of the U.S. and the "lack of resistance" by the Europeans,
"Iran wanted me to lift the sanctions imposed on them in order to meet. I said, of course, NO!" President Trump tweeted Friday.